Stop valve



Dec. 128 1926.

IR. FISCHBACH STOP VALVE v Alibi-qs.

Patented Dec. 28, 1926.

UNITED STATES PATENTy OFFICE.

RICHARD FISCHBACI-, OF BERLN, GERMANY.

STOP VALVE.

Original application led September 3, 1921, Serial No. 498,516, and in Germany February 19, 1921.

Divided and this application filed February 1, 1924.

This application is a division of my application Serial No. 498,516, filed September 3, 1921. p

This invention relates to stop valves of the sliding gate type, wherein the jointing plates or discs composing the gate or shutter are moved between the parallel jointing surfaces or seatings on the valve body by means of the valve spindle, without touching the seatings during the opening and closing movement of the valve.

The invention relates more particularly to the stop valves described in my corresponding patent application, Serial No. 498,516, in which the valve gate or shutter consists of two non-circular discs which are prevented by the valve casing lrom rotating, the said discs being moved into and out of contact with their seatings by means of a screw gear comprising two screw spindles which are rotated during the commencement of the opening movement and at the end of the closing movement of the valve'spindle.

According to my application above referred to, the two screw spindles are connected together by means of a bolt, a ball bearing being interposed between the oppose ing ends of the said spindles. Actual trials have proved that the bearing balls may easily be subjected to an vexcessive specific pressure when the valve discs are forcibly pressed against their seatings.

rlhe present invention has for its object to `avoid this drawback and with this object in view, the ball bearing is replaced by a roller bearing having conical bearing rollers, the apices of the conical surfaces of which coincide with the common centre of the roller races. Through this arrangement the friction is purely a rolling frictionand the pressure between the contacting surfaces is kept within admissible limits. Y

The invention is illustrated by way of eX- ample in the accompanying drawings in which Fig. 1 is a part vertical section and Fig. 2 is a cross-sectional view of the improved valve.

The valve casing a is provided at each end with a flange b, only one of which is shown in Fig. 2. Within the interior of the valve casing are the usual jointing faces or seatings a. The valve spindle (not shown) is screw-threaded and is enclosed by an internally threaded sleeve z, only the lower end of which is shown in Fig. 2, the said sleeve Serial No. 690,032.

being raised or lowered by the rotation of the valve spindle. The lower end of the sleeve c' merges into a cross beam z" provided with two bolts la. Pivoted on the bolts k are the upper ends of the two links Z the lower ends of which are pivoted on bolts m provided on two crank arms a. A loose collar or roller r is arranged on each of the bolts m in order to keep the two links at the required distance apart from each other, and to provide suitable guiding means. The cranks n, only one of which is shown, are rigidly connected to two threaded spindles a the threads on which have the same hand. The two spindles n are connected together by means of a screw bolt g and a nut g', a plurality of conical bearing rollers e being interposed between the opposing ends of the spindles n', the apices of the conical surfaces of the rollers coinciding with the common centre of the roller races. As shown in Fig'. 1, the conical bearing rollers are arranged in two concentric rows, the apices of the conical surfaces of both rows meeting at the common centres of the concentric roller races. rIhe screw threads of the two spindles engage internal screw threads formedin bushes u2, one of which is arranged at the outer end of each spindle. Each of the'non-circular valve discs o is provided withvan axial bore within which one of the bushes u, is arranged to slide, but is prevented from rotat-v ing therein relatively to the valve disc. Packing rings p are fitted into the valves discs near the edges thereof, the said packing rings being adapted to bear against the seatings a when the valve is closed. A cap u is screwed onto the outer end of each of the bushes u, and encloses the threaded portion of the spindle n', the said cap acting as the valve disc of a relief valve in a manner which will hereinafter be described. The movement of the bushes u, in the bores of the valve discs is limited at one end by means of screws y, the

the valve discs. This prevents the screws g/ from unscrewing themselves as would be the case if they were so positioned that exactly one half oic the shank were within the bore and one half within the body of the valve disc. The seatings on the caps a co-act with corresponding seatings provided on plugs fu which close the outer ends of the bores in the valve discs o and which are provided with apertures fw. Between each pair ot screws 'y Aapertures a' are provided which establish communication between the ap .e shown in Fig. l, and the valve chamber.

The valve operates in the following manner: Assuming that the valve discs have been lowered into the position shown in Fig. l, until they rest on the stops c, the seatings p will be co-axial with the seatina's a but the iuid will still flow Jfrom the pressure side round the one valve disc, as well as through the passages in in the plug o ot the said disc, gap .e and the axial apertures into the valve chamber, and subsequently in the reverse order, round the other valve disc and through the axial apertures a* therein, the gap e and apertures w to the nopressure side oit the valve. lt the spindles n be now turned by means ot the cranks n, they will screw out of the internal threads in the bushes u2 thereby displacing; the bushes, together with the caps u thereon, in an axial direction until the seatings on the caps u rest on the seatings o thereby closing` the relieving` valves. The main valve discs 0 will now also be moved until the seatings p are pressed on to the c. In this manner the sliding' stop valve is closed and the pressure side is elli/actually isolated 'from the no-pressure side. it the valve is to be opened.I that is it the rio-pref'n ure side is to be put under ypressure the spindles n are screwed into the bushes u2 by rotating the cranks n in the opposite direction and the two valve discs 0 will be free to approach one another. The fluid on the pressure side or' the valve will thereupon force the respective valve disc o of its seatinga and ow into the valve chainber, pressing against the inside ot the valve disc on the no-pressure side, thus preventing a gap forming' on the 'fio-pressure side, and keeping` the valve disc in Contact with its seating'. On the spindles a. being rotated further the valve disc on the pressure side will be caused to rest against the guiding rail e. On the spindles being' turned still further. the valve disc on the pressure side not being able to continue its axial movement owing te its resting' aaainst the rail e, the valve seating on the disc u. will be `brought out of contact with the seating;

on the plug o on the pressure side of tne valve. The relief valve of the valve disc on the no-pressure side will already have been opened because the torce pressing on it is only a traction of the pressure acting on the main valve disc o, and the fluid under pressure flowing lgradually from the valve chamber through the apertures m, through the relief valve and apertures w in the no-pressure valve disc into the no-pressure pipe line will establish equilibrium oit pressure on both sides of the valve. By this means it is possible to litt the two valve discs into the upper portion of the valve chamber without requiring any particular exertion.

The total cross sectional area o'l the apertures c as well as of the apertures w is 'kept materially smaller than that ot' the annular gaps .e tor instance halt the size of the latter. in this manner he well ground seating faces ot' the relief valves are not so quickly worn out and injured by the passing fluid, owing to the lower velocity of the latter in flowing' through the gaps. The diameter of each ot the apertures w is rather small, consequently the web ot tae seating` member o containingl the apertures to will protect the seat-ina' faces of the relief valve against dirt and other injurious matter in themanner ot a strainer.

lllhat l claim is l. A stop valve of the sliding` `gate or shutter type comprising in combination a valve casing, inlet and outlet ports, a valve seat at each of the said ports inside the valve casing, a shutter consisting of two non-circular discs intended to close said ports and shaped so as to be prevented by the valve casing from rotating', a screw gear including two screw spindles for inov ina' the valve discs into and out of contact with the valve seats and a roller bearing having conical bearing rollers interposed between opposing' ends of said screw spindles, the apices or" the conical surfaces of said rollers being arranged to coincide with the common centre of the roller races, as set forth.

2. A stop valve of the sliding` frate or shutter type comprising' in combination a valve casing, inlet and outlet ports., a valve seat at each ot' the said ports inside the valve casing, a shut-ter consisting' of two non-circular discs intended to close said ports and shaped so as to be prevented by the valve casing' from rotating, a screw gear including two screw spindles for movingV .the valve discs into and out ot contact with the valve seats and a plurality oft concentric roller bearings having conical bearing rollers interposed between opposing ends of said screw spindles, the apices ot the conical surfaces of said rollers being' arranged Ato coincide with the connnon vcentres ot the concentric roller races, as set forth.

3. il. stop valve of the sliding gate .or shutter type, comprising' the .combination with a valve casing having` inlet and outlet ports, a main valve seating at each of said ports inside the valve casing, a shutter comprising two non-circular discs for closing said ports, said dises being adapted to eooperate with the valve casing for pre-venting rotation of the discs, a screw gear comprising two spindles for moving` said non-circular discs into and out of close Contact withl the said main valve seatings, apertures provided in the noncircular discs for enabling pressure fluid to pass through the from one side thereof to the other, relief valves capable of obstructing the passage of pressure fluid through said apertures and ings for said relief va ves, of means for eennecting said relief valves to the said 'tw-o spindles of the screw-gear for enabling said spindles to withdraw said relief valves from their seatings prior to moving the non-circular discs out of contact with the main valve seat-ings and to press them on to their seatings prior to moving the non-circular discs into contact with the main valve seatings, as set forth.

l. A stop valve of the sliding gate or shutter type, comprising the combination with a valve casing having inlet and outlet ports, a main valve seating Vat each of sai ports inside the valve casing7 a shutter comprising two non-circular discs for clos said ports, Vsaid discs being adapted to cooperate with the valve casing for preventing rotation of thedislrs, a screw coniprising two` spindles for moving said nor.- cireular discs into and out of close Contact with the said main valve seat s, apertures provided in the non-circular dises for enabling pressure fluid to pass through the discs from one side thereof to the other, cavities provided in said non-circular l dises, relief valves capable of obstructing t sage of pressure fluid through sai l and seatings for said relief valves, o for connecting said relief valves to the sf" two spindles of the screw gear for enabii said spindles to withdraw said relief from their seatings prior to moving the noncircular discs out of Contact with the main valve seatings and to press them on to their seatings prior to moving the non-circular dises into contact with the main valve seatings, said means comprising bushes iii-:ed to the relief valves and having internalscrew threads adapted to engage said spindlesj said bushes being inserted in said axial c vities and capable of sliding therein.

5. A stop valve of the sliding gate or shutter type7 comprising the combination with a valve casing having inlet and outlet portsla a main valve seating at each of said ports inside the valve casing, shutter comprising two non-circular discs for closing said ports, said discs being adapted to co-operate with the valve casing for pieventingrotation of the discs, a screw gear comprising two spindles for moving said non-circular discs into and out of close contact with the said main valve seatings7 apertures provided in the non-circular discs for enabling pressure Hui d to pass through the discs from one side thereof to the other, axial cavities provided in saifl non-circular discs, relief valves capable of obstructing the passage of pressure liuid through said agliertures and seatings for said reliefva'lves, of means for connecting said relief valves to the said two spindles of the screw gear for enabling said spindles to withdraw sain relief valves from their seatings prior to moving the non-circular discs out of Contact withy the main valve seat-ings and to press them on to their seatings prior to moving the non-circular dises into contact with the ina-in valve seat-ings, said means comprising bushes fixed to the relief valves and having internal screw threads adapted to engage said spindles, said bushes being inserted in said axial cavities and capable of sliding therein, and abutment-s provided on the non-circular discs for limiting the movement of the bushes away from the relief valve seatings.

6. A stop va'lve of the sliding gate or shutter type as set forth in claim 4, having `the relief valves comprising caps which completely close the ends of the bushes, for the purpose set forth.

7. A stop valve of thesliding gate or shutter type, comprising the combination with a valve casing having inlet and outlet ports, a main valve seating at each of said ports inside the valve casing, a shutter comprising two non-circular discs for closing said ports, said discs being adapted to co-operate with the valve ycasing for preventing rotation of the discs7 a screw gear comprising two spindles for moving said non-circular discs into and out of close contact with the said main valve seat-ings7 apertures provided in the non-circular discs for enabling pressure fluid to pass through the discs from one side thereof to the other, axial bores provided in -said non-circular discs. cylindrical bushes inserted in said axial bores and having internal screw threads adapted to engage said spindles, said bushes being capable of moving axially within said bores, means for preventing said bushes from rot-ating, relief valves fixed to said bushes and capable of obstructing the passage of pressure fluid through the apertures in the non-circular discs and seatings for said relief valves.

8. A stop valve of the sliding gate or shutter type, comprising the combination with a valve casing having inlet and outlet ports, a main valve seating at each of said ports inside the valve casing, a shutter comprising two non-circular discs for 'closing said ports, said discs being adapted to co-operate with the valve casing for preventing rotation of the discs, a screw gear comprising two spindles for moving said non-circular discs into and out of close contact with the said niain valve seatings, apertures provided in the non-circular discs for enabling pressure fluid to pass through the discs i'roin one side thereof to the other. axial bores provided in said non-circular discs, cylindrical bushes inserted in said axial bores and having internal screw threads adapted to engage said spindles, said bushes being capable of' nieving axially within sai-d bores, axial grooves provided on the peripheries of the bushes, bolts screwed axially into the non-circular discs, said bolts being adapted to act as feather' keys for preventing rotation of the bushes, relief valves fixed to said bushes and capable of obstructing the passage of pressure fluid through t-he apertures in the noncircular discs and seatings for said relief valves.

9. A stop valve of the sliding gate or sluitter type, 'comprising in con'ibination a valve casinghaving inlet and outlet ports, a inain valve seating at each of said ports inside the valve casing, a shutter comprising tivo circular discs for closing said ports, said dises being adapted to (2o-operate with the valve casing for preventing rotation of the discs, axial cavities provided in said non-circular discs, a screw gear comprising two spindles for moving said non-circular discs into and out of close contact with the said inain valve seatings, plugs screwed into the non-circular discs for closing ends of the axial cavities, said plugs being provided inside the cavities with valve seatings, apertures provided in said plugs for admitting pressure fiuid into the cavities, axial passages provided in the non-circular discs for admit-ting pressure fluid froin the cavities to the inside of the valve casing, bushes inserted in said cavities and having internal screw threads adapted to engage said spindles, sai-d bushes being [capable of moving axially Within said cavities, relief valves fixed to said bushes and capable of co-operating with the valve seatings provided on the said plugs for preventing the passage of fluid through said axial passages.

lO. A stop valve oit the sliding gate or shutter type, comprising in combination a valve casing having inlet and outlet ports, a inain valve sealing at each of said ports inside the valve casing, a shutter comprising two circular discs for closing said ports, said discs lt ing adapted to co-operate with the valve casing 1for preventing rotation of the discs, axial cavities provided in said noncincular discs, a screw gear comprising two spindles for moving said non-circular discs into and out of close contact with the said inain valve seatings, plugs screwed into the non-.circular discs for closing ends of the axial cavities, said plugs being provided inside the cavities with valve seatings, apertures provided in said plugs for admitting )r sure fluid into the cavities, axial passages provided in the non-circular discs for adn'iitting pressure fluid from the 'cavities to the inside of the valve casing, bushes inserted in said cavities and having internal screw threads adapted to engage said spindles, relief' valves aed to said bushes and capable of ao-operating with the valve seatings provided on the said plugs for preventing the passage of fluid through said axial passages, said bushes being capable of moving axially within said cavities for a distance such that the circumferential area of the spaces between the relief valves and their seatings when full open is greater' than the combined cross-sectional areas of' the apertures provided in the plugs and the combined crosssectional areas of the axial passages provided in the non-circular discs, for the purpose of reducing the velocity of the pres-- sure fluid passing between the relief valves and their seatings.

ln testimony whereof naine to this specification.

RCHAR-D FISCHBACH,

have signed my 

